The invention relates to an electric incandescent lamp whose bulb has a glass pinch which is retained in a metal map cap with a rectangular cross-section, which cap is provided with outwardly bent tags at the wider sides of its end facing the bulb.
Such lamps are used, for example, as H1 and H3 motorcar lamps in motor vehicles in such a way that the lamp pinch lies with its wider sides in a horizontal plane. The tags then have the function of cutting off the light radiated by the lamp coil to the rear through an angle of 90.degree..+-.24.degree., i.e. through an angle of 45.degree..+-.12.degree. above and below the horizontal plane, respectively. In this way it is achieved that the rear section of the headlamp reflector, which contains an opening for accommodating the incandescent lamp, is not directly hit by the light from the incandescent coil.
An H3 incandescent lamp of this type is known from DE-OS 26 05 433, corresponding to U.S. Pat. No. 4,122,367, where the tags extend at right angles to the lamp axis.
EP 02 35 855 A1 discloses and H1 incandescent lamp in which the tags run at an angle of approximately 45.degree. to the lamp axis, adapting themselves basically to the more or less conical shape of the bulb end adjoining the pinch.
In both these cases it cannot be avoided that the tags are irradiated by the incandescent coil and reflect the light derived from the incandescent coil sideways onto narrowly delimited spatial sections of the headlamp reflector, from which sections it is reflected to the exterior, as undesired bright spots.
Thus, the present invention has for its object to provide an electric incandescent lamp whose tags provide rear shading through an angle of approximately 90.degree., but which prevents the bright spots from occuring.
In an electric incandescent lamp of the type described in the opening paragraph, according to the invention, this object is achieved in that the tags each have at their free ends a rim which runs at least substantially parallel to the lamp axis.
Owing to the presence of the rim, the light incident from the incandescent coil on the tags is reflected several times, so that it loses intensity and is substantially reflected back to the incandescent coil itself. In this way, the bright spots are voided.